Bonded wafer and method for producing bonded wafer

Abstract

A bonded wafer, wherein an epitaxial wafer having a heterojunction structure, in which a material with a different thermal expansion coefficient is epitaxially laminated on a growth substrate, and a support substrate are bonded via a bonding material, wherein the bonding material has an average thickness of 0.01 μm or more and 0.6 μm or less. As a result, provided is a bonded wafer and a method for producing the same that improves the film thickness distribution of the bonding material caused by the warpage of the semiconductor epitaxial substrate and the warpage that changes with thermal changes when the warped semiconductor epitaxial substrate and the support substrate are bonded together using the bonding material.

1 - 8 . (canceled) 
     
     
         9 . A bonded wafer, wherein an epitaxial wafer having a heterojunction structure, in which a material with a different thermal expansion coefficient is epitaxially laminated on a growth substrate, and a support substrate are bonded via a bonding material,
 wherein the bonding material has an average thickness of 0.01 μm or more and 0.6 μm or less.   
     
     
         10 . The bonded wafer according to  claim 9 , wherein the bonding material is of a thermosetting type and has a thermal softening point lower than a thermosetting temperature. 
     
     
         11 . The bonded wafer according to  claim 9 , wherein the bonding material comprises one or more of epoxy resin, benzocyclobutene (BCB), SOG (spin-on-glass), PI (polyimide), and fluororesin. 
     
     
         12 . The bonded wafer according to  claim 10 , wherein the bonding material comprises one or more of epoxy resin, benzocyclobutene (BCB), SOG (spin-on-glass), PI (polyimide), and fluororesin. 
     
     
         13 . The bonded wafer according to  claim 9 , wherein the bonding material is in a softened state. 
     
     
         14 . The bonded wafer according to  claim 10 , wherein the bonding material is in a softened state. 
     
     
         15 . The bonded wafer according to  claim 11 , wherein the bonding material is in a softened state. 
     
     
         16 . The bonded wafer according to  claim 12 , wherein the bonding material is in a softened state. 
     
     
         17 . A method for producing a bonded wafer comprising:
 (1) a step of producing an epitaxial wafer having a heterojunction structure by laminating a material with a different thermal expansion coefficient on a growth substrate by epitaxial growth,   (2) a step of preparing a support substrate, and   (3) a step of bonding an epitaxial growth layer of the epitaxial wafer and the support substrate via a bonding material,   wherein the bonding material has an average thickness of 0.01 μm or more and 0.6 μm or less.   
     
     
         18 . The method for producing a bonded wafer according to  claim 17 , wherein the bonding material is of a thermosetting type and has a thermal softening point lower than a thermosetting temperature. 
     
     
         19 . The method for producing a bonded wafer according to  claim 17 , wherein the bonding material comprises one or more of epoxy resin, benzocyclobutene (BCB), SOG (spin-on-glass), PI (Polyimide), and fluororesin. 
     
     
         20 . The method for producing a bonded wafer according to  claim 18 , wherein the bonding material comprises one or more of epoxy resin, benzocyclobutene (BCB), SOG (spin-on-glass), PI (Polyimide), and fluororesin. 
     
     
         21 . A method for producing a bonded wafer comprising:
 (1) a step of producing an epitaxial wafer having a heterojunction structure by laminating a material with a different thermal expansion coefficient on a growth substrate by epitaxial growth,   (2) a step of preparing a support substrate, and   (3) a step of bonding an epitaxial growth layer of the epitaxial wafer and the support substrate via a bonding material,   wherein a thermosetting material is applied and cured on the epitaxial growth layer, and the support substrate is further bonded thereon via the bonding material having an average thickness of 0.01 μm or more and 0.6 μm or less.